1. Field of the Invention
This invention relates to coke quenching systems and more particularly to a mobile coke quenching system wherein dry quenching is utilized to cool hot coke while pollutants emitted during coke pushing and quenching operations are substantially eliminated.
2. State of the Art
Growing concern over environmental pollution has focused on a number of industrial operations that result in substantial gaseous and particulate matter emissions. Receiving increasing attention are coke pushing and quenching operations, since the pollutants emitted from these operations have been reported to be potentially carcinogenic.
In the coke industry, the word "pushing" usually refers to that portion of the conventional coke-making process during which hot, incandescent coke is discharged from a coke oven into a mobile receiving car, or quench car, which is located adjacent the oven. As the coke falls into the quench car, it breaks up and a substantial quantity of highly polluting emissions is generated. These emissions continue as the quench car transports the hot coke to a quench tower.
The word "quenching" usually refers to that portion of the coke-making procedure during which a quench car is at rest under a "quench tower" while the incandescent coke contained in the quench car is doused with tons of water. During this wet quenching operation, large amounts of air polluting emissions are generated by the reaction of the quench water and the incandescent coke. These emissions rise into the atmosphere together with the large volumes of steam which are also generated during the operation.
In one conventional method of controlling emissions resulting from coke quenching operations, coked coal is pushed from a coke oven into the bed of a special "hooded" quench car. The quench car is typically provided with a draft-inducing mechanism for drawing these emissions upwardly from the quench car into a collection hood which overlies the car. The collected emissions are then passed through a gas cleaning system in which the pollutants are removed. A wet scrubber system is normally used for this purpose. A quench car of the type just described is taught by the J. E. Allen U.S. Pat. No. 3,843,461 and by the J. E. Allen et al U.S. Pat. No. 3,869,352.
In another type of mobile quench car, after the hot coke has been pushed into the car, it is cooled by introducing steam or inert gases from a source external to the quench car to the bottom of the closed car. The gases rise upwardly through the hot coke and are discharged to the atmosphere through a vent or waste gas stack located at the top of the car. A quench car of this type is taught by the Hughes U.S. Pat. No. 2,795,539.